Light-emitting diodes (LEDs), due to such electrical and optical advantages as low energy consumption, long service life, good stability, small size, fast response and stable luminous wave length, are widely applied in fields like lamination, household appliance, display and indicator.
A p-side-up AlGaInP-based light-emitting diode appears with the development of substrate transfer technology. In such kind of light-emitting diode, the growth substrate is removed through twice substrate transfer. A conductive substrate is bonded with one side of the n-type semiconductor, and a bonding pad electrode 142 and an extended electrode 141 are arranged on the surface 120a of the p-type semiconductor. Large power devices usually adopt enclosed designs for the bonding pad electrode and the extended electrode, as shown in FIG. 1. During fabrication, the bonding pad electrode and the extended electrode are simultaneously fabricated on the p-type semiconductor and thermally treated under high temperature to form ohmic contact, followed by substrate bonding to realize low-temperature bonding of the substrate. This avoids the influence of high-temperature thermal treatment on the substrate bonding and on the reflectivity of the reflective substrate.